The present invention relates to a GPS (Global Positioning System) receiver and a navigation device utilizing the GPS receiver.
The GPS receiver continuously receives signals put out from at least three GPS satellites. Further, every predetermined period of time (e.g., per one second), the GPS receiver measures distances up to each of the three GPS satellites and a change rate of those distances, thereby generating GPS data including a current position and a traveling direction (orientation). The GPS receiver also performs filtering with respect to the GPS data thus sequentially generated, and generates positioning data to be outputted to a navigation device and the like. For example, a least-squares method is applied on a predetermined number of GPS data items, which have been generated within a predetermined period of time, and a result of the least-squares method is outputted as positioning data. As an apparatus for performing such a filtering, Kalman filter is well known.